iMac G4 20 inch with 2GB RAM

Hey guys, I just acquired a 20 inch imac g4 and currently it has less than a gig of ram running it. I did a fresh install of osx 10.4 and it is currently running pretty decently. However, I had a couple questions for those of you with g4 experience.

I know that Apple says the imac g4 supports 1gb of ram but unofficially it will support 2 gigs. So my first question is should I bother changing out the ram on top of the logic board? Or should I stick with the easy to change ram on the bottom of the machine. Right now the machine is running on 762mb I think? Something close to that. I am quite sure that I could change the ram on the logic board, I am fairly experienced with hardware. Is it worth the time and money to upgrade to 2 gigs?

My second question is about the OS. Should I upgrade to Leopard? My very first mac was running 10.5 and I loved it, so part of me wants to upgrade to Leopard purely out of nostalgia. If I do upgrade to Leopard though, I will almost certainly need the extra 2 gigs of ram. Tiger is definitely a good OS, but if I upgrade to Leopard I can run cs4 and a better version of firefox.

I need some opinions before I start taking the machine apart and reinstalling the OS. Thanks in advance for your help.

 

I was just going to buy the ram OWC recommends to replace it with. Is there something else I should use? Also, when you say thermal paste, I only need to replace that if I upgrade the RAM on top of the logic board correct? And one more question, should I replace the PRAM battery?

 

Ahh, now that you say that it sounds like the PRAM battery may already be dead. I just acquired the machine this morning, I've been working on it all day. So you don't think I should crack it open and replace the SODIMM ram card? I suppose as long as leopard would run effectively it would be fine. I just want to remove as much lag as possible when doing day to day tasks.